The global uniform classification of organic peroxides in hazardous chemicals
Issuing time:2019-07-15 17:08
(1) the definition
Organic peroxides are liquid or solid organic compounds that contain -o-o-structures and may be considered derivatives of one or two hydrogen atoms of hydrogen peroxide that have been replaced by organic groups.The term also includes organic peroxide formulations (mixtures).Organic peroxides are thermally unstable substances or mixtures that can undergo exothermic self-accelerating decomposition.In addition, they may have one or more of the following properties:
1) easy to explode and decompose.
2) rapid combustion.
3) sensitive to impact or friction.
4) dangerous reactions with other substances.
In laboratory tests, organic peroxides are considered to have explosive properties because they are prone to deflagration, rapid burst, or show violent effects when heated under limited conditions.
The available oxygen of organic peroxide when the content of organic matter is no more than 1.0% of hydrogen peroxide, or the available oxygen of organic peroxide when the content of organic matter is no more than 1.0% but no more than 7.0% of hydrogen peroxide, is not included in the classification of organic peroxide.
-- type A can cause explosion when heated
Any organic peroxide mixture, packaged and capable of rapid deflagration or bursting, will be classified as organic peroxide type A.
Type B burns or explodes when heated
Any organic peroxide mixture that is explosive, packaged, neither deflagration nor rapid ignition, but prone to thermal explosion within the package will be classified as organic peroxide type B.
-- C and D combustion by heat
Any organic peroxides that are explosive will be classified as organic peroxides type C when the substance or mixture is not deflagrated or explodes rapidly in the package or occurs thermal explosion.Any organic peroxide that has one of the following conditions when tested in the laboratory will be classified as organic peroxide type D:
1) partial deflagration during heating under airtight conditions, no rapid outburst and no severe influence;or
2) no deflagration, slow abrupt combustion and no severe influence are shown during heating under airtight conditions;or
3) no deflagration or sudden combustion and moderate influence on display when heated under airtight conditions.
-- type E and type F combustion by heat
Any organic peroxides that do not deflagrate or burst when heated in a confined environment in laboratory tests and show little or no effect will be classified as organic peroxides type E;Any organic peroxides that are neither deflagrated nor burst when heated under airtight conditions in laboratory tests, showing only minor or no effect and low or no explosive force will be identified as organic peroxides type F.
-- no applicable label elements for type G
Any organic peroxides in laboratory tests, when heated in air under airtight condition not explosion and deflagration and showed no effect and no any explosive force, if it is thermal stable (about 50 kg packing since accelerate the decomposition temperature of 60 ℃ or higher), and the liquid mixture, diluent for desensitization role of not less than 150 ℃, boiling point will be identified as organic peroxides G type.If the mixture is not thermally stable or the boiling point of a diluent for desensitization is below 150 ° c, the mixture shall be identified as organic peroxide type F.
The available oxygen content (X) of the organic peroxide mixture can be calculated by formula (3-2).
2) (3 -
Where, ni- the number of peroxide groups of organic peroxides I per molecule;
Ci - mass fraction of organic peroxide I;
Relative molecular mass of mi- organic peroxide I.
(3) pictogram of organic peroxide risk =